Treatment of textile materials



Patented May 10, 1949 TREATMENT OF TEXTILE MATERIALS Donald H. Powers,Rossin, Melrose,

Winchester, and Elmer H. Mass., assignors to Monsanto Chemical Company,St. Louis, Mo., a corporation of Delaware No Drawing. ApplicationDecember Serial No. 632,286

14 Claims. 1

This invention relates to improved textile fln-' ishing materials andmethods of treating yarns and fabrics therewith. a

It is common practice to treat yarns and fabrics with starch solutionsin order to impart a relatively stiflened finish thereto. Starchedfabrics however lose their stiffened character and appearance after asingle washing, and also tend to dust out. In the case of yarns thestarch is applied primarily as a size for assisting in the weavingoperation, but here also the effect of the starch is markedly diminishedby the unstable character of the coating.

It is a primary object of the present invention to provide asubstantially permanent stiffened finish on fabrics which cannot beappreciably removed by ordinary washing operations and is substantiallyfree of dusting. A further object of the invention is to provide amethod of finishing fabrics which involves applying the finishing agentto the warp yarns prior to weaving, whereby the weaving operation isfacilitated and a suitably finished fabric is obtained without furthertreatment.

In accomplishing the above objects the yarn or fabric is treated with anaqueous solution or dispersion of an ammonium or amine salt ofcopolymerized styrene maleic anhydride and formaldehyde, after which theyarn or fabric is heated. This causes the styrene maleic anhydridecopolymer to react with the formaldehyde, thereby insolubilizing thecopolymer so that most of it remains on the fabric after washing andprovides a substantially permanent finish. Instead of formaldehyde,water-soluble formaldehyde-yielding substances, such as water-solublepolymers of formaldehyde which decompose on heating to yieldformaldehyde, may be used, for example, trioxane, paraformaldehyde andthe like. Suitable ammonium or amine salts of the copolymer include thesalts of ammonia, guanidine, alkylamines, such as methyl, butyl and amylamine, and quaternary ammonium hydroxides, such as phenyl trimethylammonium hydroxide,

In treating the fabric in the manner described above, it is preferableto keep the solution or bath below 180 F. to avoid appreciable reactiontaking place during the impregnation of the fabric. However, the bathmay be kept at somewhat higher temperatures for short periods withoutharmful effect. Upon removal from the bath, the fabric is heated at anelevated temperature until it is dry. Preferably, the fabric is heatedat 250 to 300 F., but satisfactory results may be obtained attemperatures as low as 200 F. The

2 concentration of the styrene maleic salt in the bath and the pick-upshould be adjusted to deposit on the fabric from 2 to by weight of thestyrene maleic salt, but preferably between about 4 and 7%. Theformaldehyde or formaldehyde polymer is ordinarily added in amountsvarying between 1 and on the weight of the styrene maleic salt.

Instead of using solutions containing both the anhydride salt and theformaldehyde, separate solutions of the two ingredients may be prepared,

after which the yarn or fabric may be treated in any order orsimultaneouslytherewith. Also, the formaldehyde may be applied in theform of a gas. It is desirable to have the bath or solution, or the gas,at slightly elevated temperatures to insure uniform penetration, butgood results may also be obtained at room temperatures.

The copolymer of styrene and maleic anhydride used in accordance withthis invention is a wellestablished product which may be prepared inseveral ways. One of the well-known methods is mass polymerization,which involves heating styrene and maleic anhydride at temperaturesbetween about and 300 F. for several hours or more. Preferably, thematerials are heated cautiously, as in a water bath. Another methodwhich may be used is known as the solvent process which involvesreacting the styrene and maleic anhydride at slightly elevatedtemperatures in the presence of a solvent which is capable of dissolvingboth the starting materials and the finished polymer, such as acetone.If desired, the copolymerization may be carried out in the presence of acatalyst, such as benzoyl peroxide.

The copolymer of styrene and maleic anhydride produced by either of theabove or by any other well-known method of manufacture is soluble inacetone, but insoluble in alcohol or benzene, and forms water-solublesalts of ammonia or alkali metals. Instead of styrene, substitutedstyrenes, such as methyl or butyl styrene, chlorstyrene or the like, maybe used to prepare copolymers which are soluble in dilute aqueoussolutions of alkali or ammonia. Instead of maleic anhydride, partiallysuch as the half ester esterified maleic anhydride, of isopropylmaleate, may be used. It is also possible to prepare and use inaccordance with this invention copolymers of styrene and maleicanhydride which havebeen copolymerized with relativeiy small amounts'ofother unsaturated compounds, such as vinyl acetate, vinyl chloride,vinyl ethy1 ether, indene, vinyl-methyl ketone, acrylic esters and thelike.

A further understanding of the invention will be obtained from thefollowing examples, the parts being given by weight:

Example I A solution of an ammonium salt of styrene maleic anhydrideresin was prepared by mixing together 600 parts of styrene maleicanhydride, prepared by copolymerizing equimolecular quantities ofstyrene and maleic anhydride at about 200 F. in a water bath, 400 partsof 26% NHiOH' and 9000 parts of water. The resulting mixture was thenheated to 200 to 212 F. with stirring, and maintained at thistemperatureuntil a uniform, somewhat viscous transparent'solutionresulted. This required about one hour. After cooling the solution toabout 120 F., a quantity of 35% formalin was added to the extent ofabout 10% on the weight of the styrene maleic anhydride used.

Heavy cotton sheeting was dipped in the bath prepared as describedabove, after which it was passed through a padder adjusted for 100%pick-up. The bath was maintained at about 120 F. during the treatment ofthe fabric to insure uniform penetration. then heated for'about two anda half minutes on a tenter frame using hot air at 300 F., at which timeit was substantially dry. The dry sheeting was washed for one hour atthe boil in a running suds, and was found to retain 95% of the depositedresin.

Example [I A solution of an ammonium salt of styrene maleic anhydrideresin, containing 10% by weight of 35% formalin was prepared asdescribed-in Example I. The resulting solution was then poured into thesize box of a slasher, after when 1 a warp of iii/single cotton yarn waspassed though the solution and dried on dry cans in the usual manner,using 12 pounds of steam. Thetreated yarn was then rolled up on a beamand woven. Excellent weaving was obtained and the resulting fabricpossessed a desirably stiffened finish which retained its stiffenedcharacter even after washing. Moreover, the fabric had an unusuallysmooth feel and did not dust out.

Example 111 mixture was then heated to 200 to 212 F. with' stirring,'and maintained at this temperature until a uniform, somewhat viscoustransparent solution resulted, which required about one hour.

After cooling the solution to about 120 F., trioxane was added to theextent of about 5% on the weight of the styrene maleic anhydride used.

Spun viscose rayon fabric was dipped in the bath prepared as describedabove, after which it was passed through a padder adjusted for 100%pick-up. The bath was maintained at about 120 F. during the treatment ofthe fabric to insure uniform penetration. The treated fabric was thenheated for about four minutes on a tenter frame using hot air at 250 F.,at the endof which time it was substantially dry. The dry fabric wasleached for one-half hour at 150 F. in tap water, and wasfound to retainabout 95% of the deposited resin.

The treated sheeting was 4 Example IV Samples of acetate rayon, nylonand glass yarns were treated in the same manner as the cotton yarn inExample II. In each case a uniformly sized warp was obtained which wasreadily woven.

The resulting fabric were smooth, full and somewhat stiffened andretained these characteristics after washing.

Although the examples refer to the treatment of cotton, viscose rayon,acetate rayon, nylon and glass, equally good results can be obtainedwith linen, flax, hemp, jute, ramie, wool, silk, cuprammonium rayon, thecopolymer of vinyl chloride and vinyl acetate, and casein,'and mixturesor blends of any of the above materials.

By treating fabrics with the finishing agents described herein, asubstantially permanent, stifiened finish is obtained, due to the factthat only relatively small amounts of the dried and reacted resin arelost on washing, 1. e. of the order of 2 to 10%. The finished fabric isalso smooth and substantially free of dusting in contrast to v thewell-known starch treated fabrics. When the resin is applied to the warpyarn and insolubilized thereon, there is the further advantage that theweaving operation is improved owing to the higher tensile strength ofthe yarn, its increased resistance to abrasiomandits generally stiffenedcharacter. The fabric from treated yarn'may have the desired finishcharacteristics without further treatmentjbut if desired it may besubjected to additional finishing operations.

, It is customary to apply the sizing or finishing I materials describedherein to yarns or fabrics.

' However, it is possible to obtain similar results by treating fibers,either initially or at any stage oftheir processing prior to spinning,after which the fibers may be spun and woven to obtain fabrics of thedesired finish characteristics. Yarns prepared from such treated fibersmay also be readily woven. It is also possible to treat in accordancewith this invention fibers which are to be used as such, .as for examplein cotton batting, or in the preparation of non-woven fabrics. -It isbelieved that the reaction between the polymerized styrene maleicanhydride salt and the formaldehyde involves or consists of a crosslinking between the styrene maleic anhydride polymer and theformaldehyde. It should be understood however that the invention is notpredicated on this or any other similar theory, and regardless of thetype of reaction which takes place the polymeric resin salt becomesinsolubilized on the yarn or fabric with the formation of a relativelypermanent size or finish. It should also be understood that the aqueoussolutions referred to in the appended claims are intended to includeaqueous dispersions, as it is possible that the ammonium or amine saltsin the solutionare actually present in the form of a colloidaldispersion.

What we claim is:

1. The method of finishing textile fabrics which comprises treating thefabric with an {in amounts varying between 1 and 20% on the weight ofsaid salt and then drying the fabric,

whereby said treating agents eact to form an insoluble resin on thefabric.

2. The method of finishing textile fabrics which comprises treating thefabric with an aqueous solution of a substance selected from the groupconsisting of formaldehyde and watersoluble polymers of formaldehyde anda salt of copolymerized styrene maleic anhydride selected from the groupconsisting of ammonium salts and amine salts, said salt being depositedon the fabric in amounts varying from 2 to 15% by weight, said substancebeing added in amounts varying between 1 and 20% on the weight of saidsalt, and then drying the fabric, whereby said treating agents react toform an isoluble resin on the fabric.

3. The method of finishing textile fabrics which comprises treating thefabric with an aqueous solution of an amine salt of copolymerizedstyrene maleic anhydride and formaldehyde, said salt being deposited onthe fabric in amounts varying from 2 to 15% by weight, said formaldehydebeing added in amounts varying between 1 and 20% on the weight of saidsalt, and then drying the fabric, whereby said treating agents react toform an insoluble resin thereon.

4. The method of finishing textile fabrics which comprises treating thefabric with an aqueous solution of an ammonium salt of copolymerizedstyrene maleic anhydride and formaldehyde, said salt being deposited onthe fabric in amounts varying from 2 to 15% by weight, said formaldehydebeing added in amounts varying between 1 and 20% on the weight of saidsalt, and then drying the fabric, whereby said treating agents react toform an insoluble resin thereon.

5. The method of finishing textile fabrics which comprises treating thefabric with an aqueous solution of an ammonium salt of copolymerizedstyrene maleic anhydride and trioxane, said salt being deposited on thefabric in amounts varying from 2 to 15% by weight, said trioxane beingadded in amounts varying between 1 and 20% on the weight of said salt,and then drying the fabric, whereby said treating agents react to forman insoluble resin thereon.

6. The method of finishing textile fabrics which comprises treating thefabric with an aqueous solution of an ammonium salt of copolymerizedstyrene maleic anhydride and paraformaldehyde, said salt being depositedon the fabric in amounts varying from 2 to 15% by weight, saidparaformaldehyde being added in amounts varying between 1 and 20% on theweight of said salt, and then drying the fabric, whereby said treatingagents react to form an insoluble resin thereon.

7. The method of finishing textile fabrics which comprises treating thefabric with an aqueous solution of an ammonium salt of copolymerizedstyrene maleic anhydride and formaldehyde,

said salt being deposited on the fabric in amounts varying from 2 to 15%by weight, said formaldehyde being added in amounts varying between 1and 20% on the weight of said salt, and then drying the fabric, wherebysaid treating agents react to form an insoluble resin thereon.

8. The method substantially as described in claim 7, but furthercharacterized in that the fabric is impregnated with the solution at atemperature below F. and is dried by heat- 6 ingforashortperiodoftimeattemperatures between 200 and 300 F.

9. The method of preparing and finishing textile fabrics which comprisestreating warp yarn with an aqueous solution of a substance selected fromthe group consisting of formaldehyde and water-soluble polymers offormaldehyde and a salt of copolymerized styrene maleic anhydrideselected from the group consisting of ammonium salts and amine salts,said salt being deposited on the fabric in amounts varying from 2 to 15%by weight, said substance being added in amounts v ying between 1 and20% on the weight of said salt, then drying the yarn, whereby saidtreating agents react to form an insoluble resin thereon, and weavingthe resulting yarn into a fabric.

10. The method of sizing textile warp yarns which comprises treatingsaid yarns with an aqueous solution of a substance selected from thegroup consisting of formaldehyde and watersoluble polymers offormaldehyde and a salt of copolymerized styrene maleic anhydrideselected from the group consisting of ammonium salts and amine salts,said salt being deposited on the fabric in amounts varying from 2 to 15%by weight, said substance being added in amounts varying between 1 and20% on the weight of said salt. and then drying the yarn, whereby saidtreating agents react to form an insoluble resin thereon.

11. In the manufacture of textile yarns and fabrics from fibrousmaterials, the steps of treating said fibrous materials at some stage oftheir processing prior to spinning with an aqueous solution of asubstance selected from the group consisting of formaldehyde andwater-soluble poly-.

mers of formaldehyde and a salt of copolymerized styrene maleicanhydride selected from the group consisting of ammonium salts and aminesalts, said salt being deposited on the fabric inamounts varying from 2to 15% by weight, said substance being added in amounts varying between1 and 20% on the weight of said salt, and then drying the fibersthus'treated, whereby said treating agents react to form an insolubleresin thereon.

12. The method of sizing or finishing textile materials, such as fibers,yarns and fabrics, which comprises treating said material with anaqueous solution of a substance selected from the group consisting offormaldehyde and water-soluble polymers of formaldehyde and a salt of acopolymer prepared by copolymerizing a substance selected from the groupconsisting of styrene and substituted styrenes with a substance selectedfrom the group consisting of maleic anhydride and partial esters ofmaleic anhydride, said salt being selectedfrom the group consisting ofammonium salts and amine salts, and being deposited on the fabric inamounts varying from 2 to 15% by weight, said substance being added inamounts varying between 1 and 20% on the weight of said salt and thendrying the treated material, whereby said treating agents react to forman insoluble resin thereon.

13. A finishing composition for textile fibers, yarns or fabrics whichcomprises an aqueous solution of a substance selected from the groupconsisting of formaldehyde and water-soluble polymers of formaldehydeand a salt of copolymerized styrene maleic anhydride selected from thegroup consisting of ammonium salts and amine salts, said substance beingpresent in an amount varying between 1 and 20% on the weight of saidsalt.

14. A textile fabric impregnated with a salt of copolymerized styrenemaleic anhydride selected from the group consisting of ammonium saltsand amine salts, which salt has been cross linked with a substanceselected from the group consisting of formaldehyde and water-solublepolymers of formaldehyde, said salt being deposited on the fabric inamounts varying from 2 to 15% by weight, said substance being present inamounts varying between 1 and 20% on the weight of said salt.

DONALD H. POWERS. ELMER H. ROSSIN.

REFERENCES CITED 'The following references are of record in the .file ofthis patent:

Number Number 592,233

a 8- UNITED STATES PATENTS Name Date Y Simmons Aug. 22,'1933 Voss et al.July 14, 1936 Bock et a1. May 12, 1942 Hopfi'et a1. Sept. 26, 1944FOREIGN PATENTS Country Date e Germany Feb. 3, 1934

